The present invention relates to alkylated diphenyloxide derivatives. In another aspect the invention relates to a specific method of making alkylated diphenyloxide derivatives, which method allows one to produce products having a wide range of viscosities.
Alkylated diphenyloxides have numerous applications such as dielectric agents in transformers, condensers, and other electrical equipment and as plasticizers, for resins, especially for cellulosic resins. Examples of some of such uses are disclosed in U.S. Pat. No. 2,604,413 and U.S. Pat. No. 4,054,937, the disclosures of which are incorporated herein by reference.
U.S. Pat. No. 2,170,809 of Coleman et al disclosed preparing such compounds by the reaction of a diphenylether with a diisobutylene in the presence of a Lewis acid "Friedel-Crafts" type catalyst, such as, for example, AlCl.sub.3. U.S. Pat. No. 4,159,390 of Klingel et al discloses that a particular type of workup procedure allows one to obtain lower viscosity products than those reported in the literature for the Coleman et al products.
The present inventors have found that when an isoolefin is employed in excess with respect to the ether in the AlCl.sub.3 catalyzed reaction, varying the molar ratio of the olefin to the ether has little significant effect on the viscosity of the final alkylated diphenyloxide. In addition, the present inventors have not found it possible to make alkylated diphenyloxide having the higher viscosities reported in U.S. Pat. No. 4,159,390 using AlCl.sub.3 as the catalyst.
One object of the present invention is to provide a technique for the alkylation of diphenylether in which the viscosity of the material having a boiling point above 180.degree. C. at 5 torr can be varied by varying the molar ratio of the iso-olefin to the ether.
Another object of the present invention is to provide a technique for producing alkylated diphenyl oxide that has a reasonably low pour point.
Still another object of the present invention is to provide a technique for readily separating the alkylated diphenylether from the reaction product mixture.
Still another object is to provide an alkylated diphenyloxide product useful as a plasticizer and as an electrical component.